The speakers are Thomas Insel who is the Director of the National Institute of Mental Health, Li-Huei Tsai who is Professor of Pathology in Harvard Medical School and Kerry Ressler who is Assistant Professor in Emory University School of Medicine.

How do we distinguish our friends from foes? How does dementia destroy memory? And how can past experience invade the present with destructive force? Scientists are closing in on the biochemical roots of these neurological puzzles.
Thomas Insel describes the profound impact of a small group of neuropeptides on social behavior in animals, from worms to humans. Oxytocin, the hormone which turns on maternal behavior and cognition, turns out to play a large role in determining social memories.

Alzheimer’s Disease (AD), which afflicts 20 million people worldwide, begins by literally clogging and tangling the hippocampus, the part of the brain essential for learning and memory. Li-Huei Tsai and other researchers have found "compelling evidence" that a small protein may be critically important in activating AD’s awful atrophy of memory.

Why is it that only some people exposed to a shocking event develop post-traumatic stress disorder (PTSD)? Kerry Ressler’s research posits that some kind of learning must take place in the brain’s amygdala -- its fear response center—that cannot readily be extinguished. Researchers have tracked down a molecular factor that increases "after learning of fear or extinction of fear." He believes that if this molecule is somehow blocked from doing its job, then someone suffering from PTSD cannot extinguish fear.

Thomas Insel is the Directo of the National Institute of Mental Health.

Li-Huei Tsai is Professor of Pathology in Harvard Medical School and Investigator, Howard Hughes Medical Institute

Kerry Ressler is Assistant Professor in the Department of Psychiatry and Behavioral Sciences, Center for Behavioral Neuroscience, Emory University School of Medicine.